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Finding the Fourth Proportional to 785.47, 1,178.07 and 439.15

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Solution

The fourth proportional to 785.47, 1,178.07 and 439.15 is: 658.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    785.47 : 1,178.07 = 439.15 : x
  2. Step 2: Convert to fraction form
    785.47/1,178.07 = 439.15/x
  3. Step 3: Cross multiply
    785.47x = 1,178.07 × 439.15
  4. Step 4: Simplify right side
    785.47x = 517,349.44
  5. Step 5: Solve for x
    x = 517,349.44/785.47
  6. Step 6: Final answer
    x = 658.65

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.